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1.
Biomed Environ Sci ; 32(8): 602-613, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31488236

RESUMO

OBJECTIVE: To comparatively study the toxicity of four metal-containing nanoparticles (MNPs) and their chemical counterparts to the air-blood barrier (ABB) permeability using an in vitro model. METHODS: ABB model, which was developed via the co-culturing of A549 and pulmonary capillary endothelium, was exposed to spherical CuO-NPs (divided into CuO-40, CuO-80, and CuO-100 based on particle size), nano-Al2O3 (sheet and short-rod-shaped), nano-ZnO, nano-PbS, CuSO4, Al2(SO4)3, Zn(CH3COO)2, and Pb(NO3)2 for 60 min. Every 10 min following exposure, the cumulative cleared volume (ΔTCL) of Lucifer yellow by the model was calculated. A clearance curve was established using linear regression analysis of ΔTCL versus time. Permeability coefficient (P) was calculated based on the slope of the curve to represent the degree of change in the ABB permeability. RESULTS: The results found the increased P values of CuO-40, CuO-80, sheet, and short-rod-shaped nano-Al2O3, Al2(SO4)3, and Pb(NO3)2. Among them, small CuO-40 and CuO-80 were stronger than CuO-100 and CuSO4; no difference was observed between Al2(SO4)3 and sheet and short-rod-shaped nano-Al2O3; and nano-PbS was slightly weaker than Pb(NO3)2. So clearly the MNPs possess diverse toxicity. CONCLUSION: ABB permeability abnormality means pulmonary toxicity potential. More studies are warranted to understand MNPs toxicity and ultimately control the health hazards.


Assuntos
Barreira Alveolocapilar/metabolismo , Nanopartículas Metálicas/toxicidade , Células A549 , Epitélio/metabolismo , Humanos , Tamanho da Partícula , Permeabilidade
2.
Nanoscale ; 3(4): 1887-93, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21424000

RESUMO

Using Cd(NO(3))(2)·4H(2)O as a precursor and ethanol/water as the solvent, we synthesized Cd(5)(OH)(8)(NO(3))(2)(H(2)O)(2) nanowires and nanobelts through a simple solvothermal method. Unlike the conventional oil-water surfactant approach, the adopted method is biologically safe, simple and environmentally benign. The morphology and size of the obtained materials were studied by FESEM. The results revealed that it is possible to assemble nanowires into microblocks by changing the ethanol/water ratio. Furthermore, the results of XRD investigation suggested that the change of ethanol/water ratio can have an influence on the crystalloid phases of Cd(5)(OH)(8)(NO(3))(2)(H(2)O)(2). Through calcination of the as-synthesized compounds in air, nanoporous CdO can be generated. We found that the as-obtained CdO materials are photocatalytically active in the degradation of methylene blue. It is envisaged that this environmentally benign method is also suitable for the synthesis of nanostructures of other oxides such as MgO and CuO.


Assuntos
Compostos de Cádmio/química , Compostos de Cádmio/síntese química , Cristalização/métodos , Química Verde/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nitratos/síntese química , Óxidos/química , Catálise , Luz , Teste de Materiais , Tamanho da Partícula , Porosidade , Solventes , Propriedades de Superfície
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 68(5): 1164-9, 2007 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-17482869

RESUMO

The interaction of a cationic water-soluble porphyrin, 5,10,15,20-tetrakis [4-(3-pyridiniumpropoxy)phenyl]porphyrin tetrakisbromide (TPPOC3Py), with anionic surfactant, sodium dodecyl sulfate (SDS), in aqueous solution has been studied by means of UV-vis, (1)H NMR, fluorescence, circular dichroism (CD) spectra and dynamic laser light scattering (DLLS), and it reveals that TPPOC3Py forms porphyrin-surfactant complexes (aggregates), including ordered structures J- and H-aggregates, induced by association with surfactant monomers below the SDS critical micelle concentration (cmc), and forms micellized monomer upon the cmc, respectively. The position of TPPOC3Py in the micelle is determined, which is not in the micelle core instead of intercalated among the SDS chains, most likely with the pyridinium group extending into the polar headgroup region of the micelle.


Assuntos
Porfirinas/química , Tensoativos/química , Água/química , Dicroísmo Circular , Luz , Espectroscopia de Ressonância Magnética , Prótons , Espalhamento de Radiação , Dodecilsulfato de Sódio/química , Solubilidade , Soluções , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 66(4-5): 1189-93, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17251055

RESUMO

The interaction of a cationic water-soluble porphyrin, 5,10,15,20-tetrakis[4-(3-pyridiniumpropoxy)phenyl]prophyrin tetrakisbromide (TPPOC3Py), with beta-CD and HP-beta-CD in aqueous solution has been studied by UV-vis, 1H NMR, 2D-NOESY and MALDI-TOF MS, and it reveals that a stable 1:1 inclusion complex between TPPOC3Py and HP-beta-CD or beta-CD has formed, in which one of the meso substituents of porphyrin ring has deeply penetrated through the cavity of HP-beta-CD from secondary face. The inclusion constants of the complexes of TPPOC3Py-beta-CD and TPPOC3Py-HP-beta-CD are (1.6+/-0.2)x10(3) M-1 and (8.9+/-0.4)x10(4) M-1, respectively.


Assuntos
Porfirinas/química , Compostos de Piridínio/química , beta-Ciclodextrinas/química , Cinética , Espectroscopia de Ressonância Magnética , Conformação Molecular , Soluções , Espectrofotometria Ultravioleta
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